Formulation of Submicro Particle Extract of Kesum Leaves (

\nThe body needs antioxidants to overcome and prevent oxidative stress. An example of a plant that has the potential to be developed because it allegedly has antioxidant activity is kesum leaves (Polygonum minus Huds.). This study aims to formulate ethanol extract of kesum leaves into submicro particle preparations with antioxidant activity. Making extracts using the maceration method with 70% ethanol solvent. The identification test of compound content was carried out qualitatively using TLC analysis and GC-MS analysis. Preparation of Kesum leaf extracts into submicron particle preparations using chitosan and sodium alginate polymers and calcium chloride (CaCl2) by ionic gelation method. Three formulas (F1-F3) were differentiated by the amount of extract 250, 500, and 750 mg for each formula. Submicro particle preparations were tested for particle size and polydispersity index and evaluated for antioxidant activity by an antioxidant test against DPPH free radical compound with quercetin as a control. Based on the TLC test, kesum leaf extract contains flavonoid compounds. GC-MS results show that kesum leaves contained octadecanoid, hexadecanoic, and cyclolongifolene oxide. The optimal formula analyzed falls into the submicron particle range, and good PDI results were obtained. The results of antioxidant activity submicro particle of kesum leaves have IC50 values of 13.3 μg/mL (F1), 6.6 μg/mL (F2), 2.6 μg/mL (F3) and is a very strong antioxidant category. It can be concluded that the ethanol extract of kesum leaves contains flavonoid and terpenoid compounds, and the preparation of a submicron-particle carrier of ethanol extract of kesum leaves has strong antioxidant activity\n